Automatic apparatus

ABSTRACT

An automatic plowing apparatus having a self-propelled vehicle carrying facing plows guided by a cable extended across a field. Opposite ends of the cable are attached to movable anchoring units which index across the field as the plowing advances. The self-propelled vehicle follows the cable extended between the anchoring units, advances the anchoring unit, and then automatically reverses itself.

United States Patent Maurice L. Peterson Kerkhoven, Minn. 806,812

. Mar. 13, 1969 Aug. 24, 197 1 Russell C. Baum Kerkhoven, Minn. a part interest inventor Appl. No. Filed Patented Assignee AUTOMATIC APPARATUS 20 Claim, 11 Drawing Figs.

Int. Cl A01b 3/68 Field of Search References Cited UNITED STATES PATENTS 509,556 11/1893 Roberts 582,237 5/1897 Schimpff 172/23 UX 1,367,127 2/1921 Culbertson..... 172/23 1,496,602 6/1924 Robinson 172/23 UX 1,503,467 8/1924 Bertella 172/23 1,743,961 1/1930 Ford........ 172/23 3,186,493 6/1965 Barry 172/2 FOREIGN PATENTS 120,459 11/1918 Great Britain 172/23 Primary ExaminerRobert E. Pulfrey Assistant Examiner-C. Coughenour 'Anomey-Burd, Braddock, & Bartz ABSTRACT: An automatic plowing apparatus having a selfpropelled vehicle carrying facing plows guided by a cable extended across a field. Opposite ends of the cable are attached to movable anchoring units which index across the field as the plowing advances. The self-propelled vehicle follows the cable extended between the anchoring units, advances the anchoring unit, and then automatically reverses itself.

PATENTED AUG24I97I 3,601. 200

SHEET 2 OF 4 66 i4 57 FIG. 5 66 /9 FIG. 4

lNvliN'luR. 62A 625 MAURICE L. PETERSON F I E. 5 BY dB/mafia? ATTORNEYS PATENTEB AUE24 l9?! (1601.200

sum 3 0F 4 MIA INVIL'N'I'UR. MAURICE L. PETERSON ATTORNEYS PATENTED Auczmsm 3, 01 200 SHEET u 0F 4 F15. J] I w INVIZN'I'UR.

MAURICE L. P ETERSON B be;

AT TORNEYS Reversible cable-operated plows have been used to plow soil without the constant. attention of an operator. Some machines have the plowing vehicle moved across the field by separate power units which have power-driven winches to pull the cable connected to the plowing vehicle. These power. units require separate motors, separate drive winches, and relative- 1y heavy cables to operate the plow. Furthermore, an operator must be present on each end of the field to realign or index the plowing vehicle and power units. Examples of these plowing systems are shown in the US. Pat. Nos. 1,367,127 to Culbertson and 1,788,604 to Vitro.

SUMMARY OF INVENTION The invention broadly relates to an automatic apparatus which has an implement-carrying vehicle operable to propel itself in opposite directions across a field. A cable extended across the field guides the vehicle between movable anchoring units located on the opposite ends of the field. Each anchoring unit has indexing structure which is actuated in response to engagement with the vehicle to move the anchoring unit to the next station so that the vehicle will advance across the field.

After the anchoring unit is indexed the drive for the vehicle is I reversed so that the vehicle propels itself to the. opposite ends of the field.

An object of the present invention is to provide an automatic earth-working apparatus which continuously works the soil and does not require the supervision of an attendant. Another object of the invention is to provide a cable-guided plowing vehicle operable to sequentially move in opposite directions across a field to plow the field without manualattention.

In the drawings:

FIG. 1 is a diagrammatic plan view of the earth-working apparatus illustrating the use and operation of the cable-guided earth-working vehicle and the indexing anchoring units;

FIG. 2 is a plan view of an anchoring unit;

FIG. 3 is a longitudinal side view .of the anchoring unit;

FIG. 4 is an enlarged view taken along line 4-4 of FIG. 2;

FIG. 5 is a plan view of the self-propelled earth-working vehicle;

FIG. 6 is a sectional view taken along line 6 of FIG. 5;

FIG. 7 is a sectional view taken along line 7- -7 of FIG. 5;

FIG. 8 is a sectional view taken along line 8-8 of FIG. 5;

FIG. 9 is a view partly in section taken along line 9-9 of FIG. 5;

FIG. 10 is a sectional view taken along line 10-10 of FIG. 5; and

FIG. 11 is a view similar to FIG. 5 showing the earth-working vehicle in return position and moving in an opposite direction.

Referring to FIG. 1 of the drawing, there is shown an automatic earth-working apparatus of the invention indicated generally at 10 located in an agricultural field 11. Apparatus 10 has a self-propelled earth-working vehicle indicated generally at 12 operatively carrying an earth'working implement 13, shown as a tilting beam two-way plow. The irnplement 13 can be a disc plow, disc, harrow, drag, planter, grain drill, crop digger, mower and like machines. Vehicle 12 propels itself in the direction of arrow 14 parallel to a first plow furrow 16 on the solid ground adjacent the worked portion of the field.

Vehicle 12 follows a cable 18 extended between anchoring units indicated generally at 19 and 21 located at opposite headlands of field 11. The vehicle 12 propels itself selectively in opposite directions along the cable 18 across the field.

When vehicle 12 reaches the end of field 11, moving in the direction of arrow 14, it will engage the anchoring unit 19. The moving energy of the vehicle 12 is utilized by. the anchoring unit 19 to index the anchoring unit in a forward direction to its next station. During the movement of the anchoring unit, it automatically reverses the drive of the earth working vehicle 12whereby the earth-working vehicle drives itself to the opposite end of the field. During the reversing of the vehicle 12, the position of the earth-working implement is changed to be operative in the direction of movement of the'vehicle 12. The indexing of the anchoring unit 19 and the reversing of the earth-working vehicle 12 is accomplished without an attendant or operator so that the entire earth-working apparatus 10 functions automatically over the width of the field 11.

Referring to FIGS. 2 and 3, there is shown an anchoring unit 19 carrying one end of the guide cable 18. The anchoring unit 21 located at the opposite end of the field has corresponding parts indicated with the same reference numerals having suffix A. The following description is limited to anchoring .unit 19.

Anchoring unit 19 has the rectangular horizontal frame 22 supported on pivoting front wheels 23 and 24 and rearwheels 26 and 27. Located longitudinally .of the frame 22 is an elongated shaft 28 having opposite ,ends rotatably mounted :on

bearing blocks 29,and 31. A first cable-storing drtrrn "32 is rotatably mounted on the rear portion of the-shaft adjacent the block 29. Drum 32 is drivably connected to the shaft :28 through a friction disc coupling 33 held in engagement with a coil spring 34. Coupling33 has a manual release lever (not shown) to disengage the friction-disc so that the cable 18 'can be extended across the field. Reverse movement of the drum 32 is prevented by a gear 36 secured to the shaft 28 cooperating with a one-way. pawl 37 pivotally mounted on the 'frame 22. An upright post 35 mounted on frame 22 adjacent drum 32 keeps cable 18 in alignment with drum 32. 1

Secured to the opposite end or forward end of the shaft 28 is a second cable-storing drum 38 for receiving a cable 39. The cable 39, shown in FIG. 3, rides on a pulley 41 and over a pulley 42rotatably mounted onthe forward end of a tongue .43 secured to the bogie structure for the front wheels 23 and. 24; From pulley 42, the cable 39 is trained around a pulley 54'." The end of-thecable 39 is secured to an anchor 46', shown in FIG. 1, located at the far side of the field :11. In use, the anchoring unit 19 is moved in a step-by-step operation about 32 inches at a time toward the anchor 46.

Returning to FIG. 3, the pulley 44 is rotatably connected to a clevis 47. A rod 48 secured to clevis 47 is slideably disposed in a tubular housing 49. Aspring Sl-biasesthe rod into the The shaft 28along with the first and second drt ms 32 and 38 is rotated in response to the movement of an actuator indicated generally at 56 mounted on a midportion of the frame 22. Actuator 56 comprises an elongated transversely PO51? tioned bar 57 slideably mounted on a transverse guideSSLRollers 59 engage opposite sides of the bar 57 to maintainthe bar on theguide 58. Secured to the back end of the bar. 57 is the plate .61 which functions as a stop for the actuator. A pair of springs 62 connected to the plate 61 and a midbeam of frame 22 biases the arm 57 in its out position as shown in FIG. The bar 57 has upwardly directed gearteeth similar to an elongated linear ratched gear. A circular gear 63 is secured to.

shaft 28 with a conventional .one-way clutch 65. The gear 63 has teeth positioned in driving engagement with the teeth on' the bar 57 whereby linear movement of thebar 57 to its in position is transformed into rotational movement of the shaft 7 28. The one-way pawl 37 acting on the gear 36 preventsrotatably attached with a bracket v66 to the outer end of the 19 isfree to move in a forward direction towards the anchor bar 57. The bumper 64 is the member that is engaged by the vehicle 12 during the indexing of the unit 19 and the reversing of the vehicle 12. i

A lever 67 pivotally mounted on the frame 22 with an upright pivot 68 is used to hold the cable 18 in alignment with vehicle 12 during the forward or indexing movement of the anchor unit 19. The outer end of lever 67 carries a roller or pulley 69 which rides on the cable 18. The opposite end of lever 67 is secured to a line or cable 71 trained about a pulley 72 mounted on frame 22 and connected to the plate 61. Movement of the actuator 56 will pivot lever 67 to hold cable 18 in alignment with the vehicle 12 being moved forward with anchoring unit 19.

Returning to FIG. 3, the cable 39 leading from the second drum 38 is extended around a guide pulley 73 which is slideably mounted in a slot 74 in'frame 22. The pulley 73 is connected to a rod 76. The rear end of rod 76 is connected to a crank arm 77 of a power transmission 78. A chain and sprocket drive 79 connects shaft 28 with the power transmission 1'8 so that on rotation of the shaft 28 the transmission 78 will reciprocate the pulley 73 along slot 74 and thereby evenly coil the cable 39 on the cable storage drum 38.

As shown in FIG. 5, the earth-working vehicle 12 has a generally l-I-shaped frame 81 fabricated from tubular material or heavy pipe. The frame is articulated so that it is movable from a right position to a left position shown in FIGS. and 11 respectively. Frame 81 has generally longitudinally side members 82 and 83 connected together with a central crossbeam assembly 84. Secured to the midsection of crossbeam assembly 84 is a longitudinal midmember 86. Crossbeam assembly 84 is pivotally connected to the side member 83 with an upright pivot 87. As shown in FIG. 7, the crossbeam assembly 84 has top and bottom end portions extended over the side member 83. The upright pivot 87 projects through the crossbeam assembly 84 and side member 83 and a reinforcing bar 88 located under and secured to the side member 83.

The opposite end of crossbeam assembly 84 carries a second upright pivot 89. The second upright pivot 89 connects thecrossbeam assembly 84 with a pair of plates 91 secured to a tubular pivot 92. The pivots 87 and 89 pivotally connect the side members 83 and 82 to the crossbeam assembly 84 so that the side members can move to their left and right dog track positions. A double-acting hydraulic cylinder90 connected to the member 86 and side member 83 is operable to pivot the side members 82 and 83 relative to the crossbeam assembly 84. Cylinder 90 is selectively actuated with a valve control 95.

As shown in FIG. 9, a horizontal tubular pivot 92 pivotally connects arms 93 and 94 joined to the side members 82A and 828 to thereby pivotally connect the side members for movement about a transverse horizontal axis. The elevation of the side members along with the elevation of the crossbeam assembly 84 is controlled by a hydraulic cylinder 96 secured to the pivotally connected side members 82A and 828 with the brackets 97 and 98. Hydraulic cylinder 96 is operable to change the earth-working position of the implement 13 by raising and lowering the center of the frame 81.

A ground-engaging control is used to activate cylinder 96 so that the earth-working tool or implement follows the contour of the ground. As shown in FIG. 5, control comprises a downwardly directed arm 99 carrying a ground-engaging wheel 101. The upper end of the arm is connected to a control unit as 102, as a valve, for regulating the flow of fluid to the hydraulic cylinder 96. As the wheel 102 follows the contour of the ground, the arm 99 actuates the control unit 102 and thereby regulates the flow of fluid to and from the hydraulic cylinder 96. The expansion and contraction of the cylinder 96 will raise and lower the crossbeam assembly 89 and thereby raise and lower the earth-working implement 13.

The frame 81 is mounted on separate drive wheels 103, 104, 105 and 106. The wheels are connected to the ends of the side members 82 and 83 and are power driven so that vehicle 12 has a four-wheel drive. All of the drive wheels are substantially identical in structure as shown in FIG. 6. The following description is limited to the drive wheel 103 shown in FIG. 6.

Wheel 103 has an inverted U-shaped yoke 107 carrying a mount the shaft 109 in the end of the side member 83 to pivot the wheel 103 about an upright axis.

As shown in FIG. 5, the arms 111 are connected to transverse tie rods 112 and 113 connected to the adjacent wheel 106 so that the wheels 103 and 106 will turn together to steer the vehicle 12. The tie rods 112 and 113 also provide rigid connections between the ends of side members 82 and 83.

Returning to FIG. 6, a drive shaft 114 rotatably mounted in the upper end of yoke 107 is connected to the axle 108 with a chain and sprocket drive 116. A universal joint 117 connected to the inner end of drive shaft 114 is connected with a suitable shaft 1 15 to the drive shaft of the wheel 106. The opposite end of drive shaft 114 is connected to a gearbox 118.

As shown in FIG. 5, a power-transmitting shaft119 is connected with suitable universal joints to the gearbox 118 and a transmission 121, as a planetary gear transmission located in the central part of the vehicle. The transmission 121 is driven by an engine 122. Engine 122 can be a'prime mover as a gasoline or diesel engine or electric motor for creating the power to drive the vehicle 12. Engine 122 in addition to supplying power to the transmission drives a hydraulic pump (not shown) for the hydraulic control system of the vehicle. Wheel 104 and wheel 105 at the opposite end of the frame 81 are connected with transmission 121 with a shaft 123 and a gearbox 124. The transmission 121 has a reversing mechanism 125 operable in response to movementof acontrol lever 126 to change the direction of drive to all the wheels 103, 104, 105 and 106. Reversing mechanism 125 is operably connected to valve control so that vehicle 12 reverses and changes dog track position at about the same time. Reversing mechanism 125 can be a conventional brake actuator for the brakes of the planetary gear transmission 121 or a valve for reversing the flow of fluid to a fluid motor transmission.

Extended transversely across opposite ends of the frame 81 are bumpers 127 and 128. Forwardly directed arms 129 position the bumpers 1'27 and 128 in front of their adjacent drive wheels. The bumpers 127 and 128 are at approximately the same elevation as the upright rollers 64 and 64A on the anchoring units 19 and 21. Pivotally mounted on the bumpers 127 and 128 are crank arms 131 and 132. Cables 133 and 134 connect the crank arms 131 and 132 to the transmission control lever 126. Each crank arm .has a forwardly directed member operable to be engaged by the roller on the anchoring unit in front of the bumper. On the movement of the anchoring unit 19 to the next index station, the roller 64 will engage and pivot the crank arm 131 moving the transmission control lever 126 to reverse the drive for the vehicle 12.

The cable-steering apparatus carried on the vehicle 12 cooperates with the cable 18 to steer the vehicle along the cable and turn the forward wheels at the end of the field to dog track the H-shaped frame 81. As shown in FIG. 5, the steering apparatus for the wheels 104 and are substantially identical with the cable-steering apparatus for the wheels 103 and 106. The corresponding steering structures for wheels 104 and 105 are identified with the reference numerals having a suffix A.

The cable 18 is threaded through two pairs of cooperating rollers 139 mounted on the top side of the crossbeam assembly 84 in the middle of the vehicle. The cable extends generally longitudinally of the vehicle adjacent an outwardly directed steering arm 141. Rollers 142 on the steering arm engage the cable 18. The steering arm 141 has a flexible neck 143, thepurpose of which will be explained hereinafter. The inner end of steering arm 141 is connected to a control valve 144 operable to regulate the flow of hydraulic fluid to a double-acting' hydraulic cylinder 146 mounted on the end of the side member 83. The piston rod of the cylinder 146 is connected to a member 147 attached to the tie rod 113. Operation of the fluid motor 146 will turn the wheels 103 and 106. Pivotally mounted on the end of the midmember 86 is a link 148 carrying a guide wheel .149 on the cable 18. A connector rod 151 joins the midportion of the link 148 to the side member 83 to hold the guide wheel 149 in general alignment with the rollers 142. The opposite end of the midmember 86 pivotally carries a similar link 152 carrying a guide wheel 153. Wheel 153 is spaced from the cable 18 whereby the cable 18 is aligned with the rollers 142A on the steering arm 141A. A connector rod 154 joins the link 152 with the side member 83.

The position of the steering arm 141 is controlled by the angular position of the H-shaped frame so that when the frame dog tracks between its left position and right position, the forward steering wheels will turn so that the forward end of the vehicle will move away from the worked soil in the direction of the movement of the anchoring unit. A cable 156 trained around a first pulley 157 secured to the side member 83 and a second pulley 158 secured to the end of side member 82 operates to move the steering arm 141 when the position of the I-l-shaped frame is changed. A connector 159 joins one end of the cable 156 to the midmember 86. The opposite end of the cable 156 is attached with a connector 161 to the end of side member 83. The cable is attached with an adjustable clamp 162 to the arm 141 below the flexible neck 143. In this manner, the cable 156 can move the arm 141 with very little movement of the steering cable 18 as the flexible neck 143 will bend.

Referring to FIGS. 5 and 10, the earth-working implement 13 is a tilting beam plow having a pair of facing plow bottoms 163 and 164 located on opposite sides of the crossbeam assembly 84. Each plow bottom may be provided with a hydraulic or mechanical trip mechanism to permit the bottom to release and pass over an obstruction. A longitudinal beam 166 is connected to plow bottom 164. In a similar manner, the longitudinal beam 167 is connected to the plow bottom 163. Beams 166 and 167 are attached to a sleeve 168 rotatably mounted on the stationary cylindrical support 172 of the crossbeam assembly 84. Sleeve 168 an arcuate cutout 169 having a circumferential distance less than 90 accommodating an upright rib or stop 171 secured to the top of the cylindrical support 172. The sleeve 168 being rotatablymounted on the cylindrical support will rotate until sides of the cutout engage the rib 171 to selectively move the plow bottoms 163 and 164 to ground-working positions and transport positions. When one bottom is in ground-working position the opposite bottom is located above the crossbeam assembly 84.

The plow bottoms are moved into the ground-working positions in response to the dog-tracking or angular movement of the H-shaped frame 81. A cable 173 wound around sleeve 168 moves the plow bottoms in response to angular movement of the frame 81. A cable fastener 174 connects one end of the cable 173 to a forward portion of the side member 83. In a similar manner, a cable fastener 176 connects the opposite end of the cable 173 to a rear portion of the side member 83. Guide rollers 177 rotatably attached to the sleeve 168 maintain the cable 173 in alignment with the sleeve 168. Referring to FIG. 11, with the vehicle 12 moving in the direction of arrow 178, the cable 173 holds the plow bottom 164 in ground-working position, the side 179 of the sleeve 168 is held in engagement with the stop 171.

In use, the anchoring units 19 and 21 are located at opposite headlands of the field 11. Their respective cables 39 and 39A are attached to anchors 46 and 46A located on the opposite side of the field. The earthworking vehicle 12 is positioned between the anchoring units and threaded onto the guide cable 18. On operation of the motor 122, all four drive wheels 103, 104, 105 and 106 operate to propel the vehicle 12 along the cable 18. The steering arms 141 and 142 operate to steer the drive wheels in the path dictated by the cable 18.

The hydraulic cylinder 90 is operable to control the angular position of the articulated frame 81 and the ground-working positions of the plow bottoms 163 and 164. With the articulated frame 81 located in the left position, as shown in FIG. 5, and the vehicle 12 moving in the direction of the arrow 14, plow bottom 163 is in plowing position while plow bottom 164 is in an elevated or transport position. The drive wheel 105 rides in the furrow 16 while the rear drive wheel 106 rides in the new furrow l7 behind plow bottom 163.

The ground-working position of the plow bottom 163 is controlled by changing the elevation of the crossbeam assembly 84. This is accomplished through the use of the hydraulic cylinder 96 and the ground-engaging control comprising the valve 102 connected to the arm 99 carrying the ground wheel 101. As the arm 99 moves with the contour of the ground, valve 102 regulates the supply of hydraulic fluid to the cylinder 96 to either raise or lower the crossbeam assembly 84.

As the vehicle 12 approaches the anchor unit 19, the bumper 127 will engage the roller 64. When the roller contacts the pad 137 the engine 122 is throttled thereby slowing down the vehicle 12. Also, actuation of the pad 137 can reduce the speed of the planetary transmission 121 to further reduce the forward motion of the vehicle 12. As the vehicle continues its movement toward the anchor unit 19, the actuator 56 is moved inwardly thereby rotating the shaft 28. The second drum 38 takes up a portion of the cable 39. The tension on cable 39 releases the brakes of the anchoring unit thereby allowing the vehicle to index or move to its next station. As the actuator 56 moves in an inward direction, the lever 67 pivots to hold the cable 18 in general alignment with the vehicle 12. The forward movement of the anchoring unit 19 carries the roller 64 into engagement with forward arm of the bellcrank 131 to trip the reversing control 126 and the valve control for the cylinder 90. This reverses the drive to all the drive wheels 103 to 106 and actuates cylinder 90 to dog track the articulated frame 81 to the right. The drivewheel moves out of the path of the furrow 16 in general longitudinal alignment with the plow bottom 164 as shown in FIG. 11. The steering of the wheels 104 and 105 is accomplished by the movement of the cable 156A. The cable 156A turns steering arm 141A in response to the angular movement of the side member 83 of the frame. As soon as the vehicle 12 moves away from the anchoring unit 19, the pressure on pad 137 is released. This permits the planetary transmission 121 and engine 122 to resume its normal speed. The transmission 121 being reversed drives the wheels 103 to 106 in reverse moving vehicle 12 to anchor unit 21.

The angular movement of the side member 83 also raises the plow bottom 163 and moves the plow bottom 164 to a ground working position. The cable 173 rotates the sleeve 168 between the stop positions relative to the rib 171.

The vehicle 12 will travel along the route of the cable 18 until it coacts with the anchoring unit 21 at the opposite end of the field. in the manner described above, the anchoring unit 21 will advance to the next index station and then automatically reverse the vehicle 12 and reverse the operation of the earth-working implement for working a new section of the field. This process is repeated until the anchoring units 19 and 21 reach their anchors 46 and 46A.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

1. An apparatus comprising: a vehicle having a frame comprising longitudinal side members and a crossmember extended between and pivotally connected to the side members, power means operable to move and hold the side members selectively in a first position and a second position, wheel anchor units to reverse the direction of drive of the vehicle and actuate the power means whereby the side members move from one position to the other position when the vehicle engages an anchor unit.

2. The apparatus of claim 1 wherein: the anchor units each have a drum for receiving the cable and a means for biasing the drum in a rotational direction to maintain tension on the cable.

3. The apparatus of claim 1 wherein: the anchor units each have'rneans to advance the unit in response to engagement of the vehicle with the unit whereby the cable is sequentially moved over the field as the earth working of the field progresses. I

4. The apparatus of claim 3 wherein: the means to advance the unit comprises a drum, a cable on the drum and connected to an anchor, and an actuator engageable by the vehicle to rotate the drum and thereby advancing the unit toward the anchor.

5. The apparatus of claim 1 wherein: The anchoring units each have advancing means to move the unit in response to movement of the vehicle toward the unit and brake means releasable in response to the advancing means to allow the unit to move.

6. The apparatus of claim 1 wherein: the implement is a first plow and a second plow positioned opposite the second plow.

7. The apparatus of claim 6 including: means to selectively move and hold the plows in earth-working positions during the reversing of the vehicle.

8. The apparatus of claim 6 wherein: said frame includes a first portion and a second portion, generally horizontal transverse pivot means connecting the first portion with the second portion and power means connected to said first portion and said second portion to raise and lower the frame to regulate the ground-working positions of the first plow and the second plow.

. 9. The apparatus of claim 8 including: a ground-contoursensing means operable to control the power means in response to the contour of the ground.

10. The apparatus of claim 1 wherein: the crossmember has a longitudinal member fixed to the midportion thereof, said power means being connected to the longitudinal member and one side member and operative to angularly move both side members relative to the longitudinal member. i

11. The apparatus of claim 1 wherein: the implement is an earth-working device connected to the crossmember.

12. The apparatus of claimll wherein: one of the side members is articulated, and means attached to the articulated.

- mitting means connecting the motor to the drive wheels.

14. The apparatus of claim 13 wherein: the means to reverse the direction of drive includes a reversing control for the power-transmitting means.

15. A vehicle operable to propel itself between anchoring units connected to each other with a cable comprising: a frame having longitudinal side members with end portions and a crossmember pivotally connected to the side members, power means operable to move and hold the side members selectively in a first position and a second position, wheel means mounted on the end portions of the'side members, motor means mounted on the frame operable to drive the wheel means to propel the vehicle between the anchoring units, means to reverse the drive direction to the wheel means, said power means and means to reverse the drive direction to the wheel means being actuated on engagement of the vehicle with an anchoring unit, and means on the vehicle engageable with the cable to guide the vehicle along the cable.

16. The vehicle of claim 15 including: a ground-working implement means mounted on said frame.

17. The vehicle of claim 16 wherein: one of said side members has a f rst portion and a second portion transverse generally horizon al pivoted means connecting the first portion with the second portion, and power means to raise and lower said first and second portions to regulate the groundworking position of the earth-working implement means.

18. The vehicle of claim 17 including: a ground-contoub sensing means operable to control the power means in response to the contour of the ground.

19. The vehicle of claim 15 including: steering means connected to the wheel means and arm means coupling the steering means to the cable whereby the cable actuates the steering means to control the direction of movement of the wheel means.

20. The vehicle of claim 15 wherein: the crossmember has a longitudinal member fixed with the midportion thereof, said power means being connected to the longitudinal member and bers relative to the longitudinal member. 

1. An apparatus comprising: a vehicle having a frame comprising longitudinal side members and a crossmember extended between and pivotally connected to the side members, power means operable to move and hold the side members selectively in a first position and a second position, wheel means mounted on the frame for supporting the frame above the ground, drive means connected to the wheel means to propel the vehicle over the ground, an implement connected to the vehicle, a first anchor unit, a second anchor unit spaced from the first anchor unit, a cable extended between the anchor units, means on the vehicle engageable with the cable to guide the vehicle along the cable between the anchor units, and means on the vehicle selectively engageable with the anchor units to reverse the direction of drive of the vehicle and actuate the power means whereby the side members move from one position to the other position when the vehicle engages an anchor unit.
 2. The apparatus of claim 1 wherein: the anchor units each have a drum for receiving the cable and a means for biasing the drum in a rotational direction to maintain tension on the cable.
 3. The apparatus of claim 1 wherein: the anchor units each have means to advance the unit in response to engagement of the vehicle with the unit whereby the cable is sequentially moved over the field as the earth working of the field progresses.
 4. The apparatus of claim 3 wherein: the means to advance the unit comprises a drum, a cable on the drum and connected to an anchor, and an actuator engageable by the vehicle to rotate the drum and thereby advancing the unit toward the anchor.
 5. The apparatus of claim 1 wherein: The anchoring units each have advancing means to move the unit in response to movement of the vehicle toward the unit and brake means releasable in response to the advancing means to allow the unit to move.
 6. The apparatus of claim 1 wherein: the implement is a first plow and a second plow positioned opposite the second plow.
 7. The apparatus of claim 6 including: means to selectively move and hold the plows in earth-working positions during the reversing of the vehicle.
 8. The apparatus of claim 6 wherein: said frame includes a first portion and a second portion, generally horizontal transverse pivot means connecting the first portion with the second portion and power means connected to said first portion and said second portion to raise and lower the frame to regulate the groUnd-working positions of the first plow and the second plow.
 9. The apparatus of claim 8 including: a ground-contour-sensing means operable to control the power means in response to the contour of the ground.
 10. The apparatus of claim 1 wherein: the crossmember has a longitudinal member fixed to the midportion thereof, said power means being connected to the longitudinal member and one side member and operative to angularly move both side members relative to the longitudinal member.
 11. The apparatus of claim 1 wherein: the implement is an earth-working device connected to the crossmember.
 12. The apparatus of claim 11 wherein: one of the side members is articulated, and means attached to the articulated side members to selectively raise and lower the earth-working implement.
 13. The apparatus of claim 1 wherein: the vehicle has drive wheels and the drive means includes a motor and power-transmitting means connecting the motor to the drive wheels.
 14. The apparatus of claim 13 wherein: the means to reverse the direction of drive includes a reversing control for the power-transmitting means.
 15. A vehicle operable to propel itself between anchoring units connected to each other with a cable comprising: a frame having longitudinal side members with end portions and a crossmember pivotally connected to the side members, power means operable to move and hold the side members selectively in a first position and a second position, wheel means mounted on the end portions of the side members, motor means mounted on the frame operable to drive the wheel means to propel the vehicle between the anchoring units, means to reverse the drive direction to the wheel means, said power means and means to reverse the drive direction to the wheel means being actuated on engagement of the vehicle with an anchoring unit, and means on the vehicle engageable with the cable to guide the vehicle along the cable.
 16. The vehicle of claim 15 including: a ground-working implement means mounted on said frame.
 17. The vehicle of claim 16 wherein: one of said side members has a first portion and a second portion, transverse generally horizontal pivoted means connecting the first portion with the second portion, and power means to raise and lower said first and second portions to regulate the ground-working position of the earth-working implement means.
 18. The vehicle of claim 17 including: a ground-contour-sensing means operable to control the power means in response to the contour of the ground.
 19. The vehicle of claim 15 including: steering means connected to the wheel means and arm means coupling the steering means to the cable whereby the cable actuates the steering means to control the direction of movement of the wheel means.
 20. The vehicle of claim 15 wherein: the crossmember has a longitudinal member fixed with the midportion thereof, said power means being connected to the longitudinal member and one side member operative to angularly move both side members relative to the longitudinal member. 